Cinematographic apparatus



Jan. 1, 1929. 1,697,758'

A. ERNEMANN CINEMATOGRAPHIC APPARATUS Filed Jan. 25 1927 /4 s'nvo'nlo'r:

Alerarizler .Ernemann- Patented Jan. 1, 1929.

' UNITED stares PATENT or fice. H

ALEXANDER ERNEMANN, or DBESDEN, GERMANY.

' CINEMATOGRAPHIG APPARATUS.

7 Application filed January 25, 1927, Serial No. 163,502, andin Germany May .6, 192 6.

The present invention relates to cinematographic apparatuses and more particularly to a film controlling device for such machines.

e In the projection of motion pictures from strip films, it is ofttimes desirable to prolong the titles or other parts of the pictures without stopping or slowing down the speed of the motor which drives the projecting apparatus and the primary purpose of the present invention is to provide a device for power driven motion picture. projecting machines whereby the speed of travel of the film through the machine may be manually controlled.

Another equally important object of the invention is to provide a mechanical brake for the film feed mechanism of motion picture apparatuses which may be readily applied to almost any of the prevalent types of machines now in use without altering the machines or interfering with the good working thereof.

Other objects of the invention will be in part obvious and in part pointed out hereinafter.

In order that the invention and its mode of operation may be readily understood by those skilled in the art, I have in the accompanying illustrative drawings and in the detailed following description based thereupon, set out one possible embodiment of the invention.

In the drawings:

Figure 1 shows in side elevation one form of the invention as applied to the driving crank of a motion picture machine, and

Figure 2 shows in side elevation another form of the invention applied to a portion of the moving picture machine and the latter being shown partly in section.

Referring now more particularly to the accompanying drawings wherein like characters of reference will designate corresponding parts throughout, the numeral 8 indicates the ordinary driving sprocket of the film winding mechanism of a motion picture projection apparatus carried by the driving shaft 12. Loosely mount-ed upon this shaft is the usual auxiliary driving crank 1 which latter carries a projection adapted to engage with the pin 18 secured to the shaft 12 so that upon rotating the crank in one direction, the shaft will rotate therewith, but as the film driving mechanism is power driven by an electric motor or the like this auxiliary crank 1 normally rests in the position as shown while the shaft is in motion. Fulcrumed as at 2 upon the crank 1 is a lever 3 and this lever 3 is provided with a hand grip at one end thereof while its opposite end has secured thereto a disc 5 adapted at times to frictionally engage a disc 7 formed with the outer end of the shaft 12. A leaf spring 4 carried by this lever 3 engages the crank 1 for normally holding the lever in the position as shown but when it is desired to slow down the speed of rotation of the power driven shaft 12 the operator gripping the handle 6 forces the disc 5 against the disc 7.

This braking attachment instead of being applied to the auxiliary driving crank of the motion picture machine may be applied to the casing 13 thereof and the brake with the driven pulley 11 of the film winding mechanism as is shown in Figure 2. Secured within the bearings 14L and 15 carried by the casing is a rotatable shaft 16 having a handle 9 secured at one end thereof and a block or brake shoe 10 secured to an arm carried by the opposite end of said shaft. A coil spring 17 is wound about this shaft 16 having one end connected thereto and its opposite end 18 30 secured to the bearing 14. whereby the brake shoe 10 will be normally retained out of contact with the pulley 11, but uponrotation of the shaft 16 by the handle 9 the brake shoe 10 will frictionally engage the pulley 11 to retard the rotation of the latter.

Method of operation. When it is desired to prolong the title or other parts of the pic-- ture upon a screen the operator by gripping the handle of either device may cause the brake shoe of such device to be brought into frictional contact with the film feeding mechanism of the projecting apparatus whereby the drawing or winding of the film through the apparatus will be retarded as long as either brake shoe is applied, but when the brake is released the winding mechanism will continue drawing the film through the apparatus.

I claim:

1. A device for retarding the film winding mechanism of a cinematographic apparatus comprising'a casing, a pulley carried by the casing and driven by the winding mechanism, a shaft rotatably mounted on the casing, a braking shoe secured to one end of the shaft and adapted upon rotation of the latter to frictionally' engage said pulley whereby to retard its movement, a spring means associated with said shaft for normally urging 110 the braking shoe out of engagement with said pulley.

2'. A device. retaizding therfilm winding HIBChRHiSIIl Oi a cinematographic apparatus comprising a casing, a pulley carried by said casing and driven by the filmwinding mechanism, relatively spaced bearings depending from the casing, a rotatable shaft received bythe bearing, a braking shoe secured to one end of said shaft and: adapted upon rotation 0i the latter to be brought, into. frictional engagement with said: driven pulley whereby to retard its movement, and a coil spring mounted on the shaft between said spaced bearing and adapted to urge the braking shoe out of engagement with the driven pulley.

In testimony whereof I aflix my signature.

' ALEXANDER ERNEMANN. 

